Oscar l



0- L. LAWSON.

LOOP SPREADER FOR SEWING MACHINES.

APPLICATION FILED MAR. 25, 1915.

Patented Aug. 15, 1916.

\X/ITNESSESI INvEMuvi I mm m UNI TAR AT @FT@.

OSCAR L. LAWSON, OF LYNN, MASSACHUSETTS, ASSIGNOR OF ONE-HALF TO CARL ANDERSON, OF LOWELL, MASSACHUSETTS.

LOOP-SPREADER FOR SEWING-MACHINES.

Specification of Letters Patent.

Patented Aug. 15, 19116.

Original application filed. May 29, 1914, Serial No. 841,752. Divided and. this application filed March 25,

To all whom it may concern:

Be it known that I, OSCAR L. LAwsoN, a subject of the King of Sweden, residing at Lynn county of Essex, State of Massachusetts, have invented a certain new and useful Improvement in Loop-Spreaders for Sewing-Machines, of which the followingis a specification, reference being had therein to the accompanying drawings.

This invention relates to sewing machines for leather work, and has particular reference to machines for sewing shoes.

The improvements described herein are designed with special reference to providing a sewing machine which shall be of low cost and which will be effective for the use of cobblers as well as for general purposes to which such leather sewing machines are put.

This application is a division of my prior application for lock stitch sewing machine filed May 29, 1914, Serial No. 841,752.

The particular object of my invention is to provide an automatic spreader to open the loop to permit the hook of the shuttle to engage the loop, together with suitable actuating mechanism therefor.

In the accompanying drawings I have shown only those parts of the machine which relates to the spreader and the actuating mechanism therefor; the other parts of the machine are shown in my said prior application to which reference may be had for further explanation.

In the drawings, Figure 1 is a side detail elevation of the loop spreader mechanism. .Fig. 2 is a front detail elevation of the loop spreader mechanism. Fig. 3 is a plan view of the parts illustrated in Fig. 2, the spreader being shown at a distance from the plane of the needle. Fig. 4 is a view similar to Fig. 3, but showing the spreader in the position it occupies at the time when the loop is laid over it.

Similar reference characters indicate the same or similar parts in all the views.

Referring now to the drawings there is shown at 30 the work support; at 31 the hooked needle; at 32 the awl, at 33 the needle carrier or segment by which the needle is moved; at 34 the needle guide; and at 35 the presser foot. The said needle seg ment is oscillated by means. of a connecting rod 38 actuated by a crank 37 on the main Serial No. 17,047.

shaft 21. These parts are in general of well known construction.

It is tobe understood of course that the machine is of the type known as awl feed. That is by suitable mechanism not necessary to describe or illustrate in detail the awl passes through a slot in the work support and is shifted when in upper position so as to feed thework along.

At 7 0 and 71 are shown two members conveniently termed the looper and hook which assist in the formation of the stitch and which in combination with other stitch forming instrumentalities form the subject matter of a companion divisional application filed March 25, 1915, Serial No. 17 ,046.

It will be understood that in the formation of the stitch, a portion of the needle thread is held between the looper and the hook in a substantially horizontal position and is thereby laid into the hook of the needle before the needle passes upward through the work. It will also be understood that this loop after being drawn through the work is composed of two substantially parallel vertical portions of the thread which are relatively close together and between which the hook of the shuttle must enter. It will be understood that the two substantially parallel sides of the loop are not at this time in actual contact with each other but are separated by a space, which, at the end of the loop which is over the needle, is equal to the thickness of the needle at the base of its barb. This space is sufficient to permit the insertion of the member by which the sides of the loop will be spread apart.

To spread the loop after the needle has risen, that is to carry one side of the loop aside as shown in Fig. 2 so that the hook of the shuttle will engage the loop and cause the loop to be carried around the shuttle, I provide a spreader 85 the said spreader being pivotally supported at 86 by a fixed stud or bracket 87. The spreader is provided with a curved extension88 and has a slot, a

portion of which is straight, as at 89; thethat the loop as it is drawn upward and backward by. the upward movement of the needle is carried over the point of the spreader with one side against its outer face; then the latter shifts aside to the position shown in Fig. 3, and holds the thread thereon for the shuttle hook to engage the loop. This loop spreader is supported at a point so far to the rear of the loop that the thread can be carried around the shuttle without the loop spreader interfering with the loop, the loop being drawn off and away from the spreaderby the action of the take-up in the ordinary manner.

As shown in Fig. 1 the tip of the loop spreader 85 extends far enough so as to pro- ,ject beyond the plane of the loop of thread carried up by the shuttle. The cam slot 89 and 90 is so formed that when the needle is rising the tip of the spreader lies close to the needle so that one side of the'loop is drawn over the outer side of the tip, and then as the needle reaches or nearly reaches the position shown in Fig. 1, the spreader begins to swing laterally to the position shown in Fig. 2. This provides an exceedingly simple device which enables the loop to be engaged by the spreader by the sim ple upward and rearward movement of the needle while the spreader itself is stationary.

What I claim is 1. A sewing machine comprising in combination stitch forming mechanism including a curved hook needle movable upwardly and rearwardly, a loop spreader pivoted in the rear of the path of movement of the needle and having a cam slot, and an oscillating pin engaging said slot.

2. A sewing machine comprising in com bination stitch forming mechanism including a curved'hook needle movable upwardly and rearwardly and including a. needle seg ment mounted on a hub, and a loop spreader pivoted to a fixed part of the machine to the rear of the hub of the needle segment, said loop spreader having a cam groove formed therein adjacent the hub of the needle segment, and a pin on said hub engaging said cam groove to move the spreader in time with the needle segment.

3. A sewing machine comprising in combination stitch forming mechanism including a curved hook needle movable upwardly and rearwardly, a loop spreader pivoted in the rear of the path of movement of the needle and having a curved extension, said spreader and extension being provided with a cam slot, and an oscillating member having a pin engaging said slot.

In testimony whereof I ailix my signature, in presence of two witnesses.

OSCAR L. LAWSON.

Witnesses:

GEORGE P. DIKE, Arron H. MORRISON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. 0. 

